Black aints killing my willow tree

Asked July 4, 2020, 11:22 AM EDT

There are aints on my willow tree, there are small wholes in the bark all over where they go in and out and some of the willow tree branches are dead . Can I still safe the tree?

St. Clair County Illinois

1 Response

If the ants are on the large side and black they are carpenter ants. The ants are not what is killing your tree but they are attracted to dead and dying wood so they will move in and set up house keeping. Your willow is subject to several plant diseases that could weaken it enough that it would have several dead and dying branches. If the tree is small the disease process may already be too far along to save it. When carpenter ants move in the tree is pretty far along in the death process.

If the ants are small they may be attracted to the sticky, sweet exudate of sap eating insects such as aphids or mealy bugs. Are leaves wilting, small branches limp and do you see any patches of a black sooty looking substance (sooty mildew which will live on the insect exudate also)? Often a stream of water can wash off aphids but if the tree is large enough this would be a daunting task.

Since you talk about seeing multiple holes and the ants going in and out it does sound more like carpenter ants. As I said they are not killing your tree but taking advantage of a severely ill or dying tree to move in, dig tunnels and create a home for their nest. If this is a significant tree in your landscape it might be worth it to have an arborist come and examine your tree and help you determine if it can be saved or if it is too far gone to save.

Sorry I can't be hopeful about the long term outcome for your tree.